On Fri, May 3, 2013 at 10:54 AM, Guy
http://hackage.haskell.org/**trac/ghc/wiki/**DefaultSuperclassInstanceshttp://hackage.haskell.org/trac/ghc/wiki/DefaultSuperclassInstances
I'm surprised that the various superclass proposals haven't got more attention, seeing as it would allow for this kind of class hierarchy clean-up without breaking lots of code.
IIRC they've been tried and found to actually cause more backward compatibility issues than they solve because there are so many packages which have created their own instances, and nobody's found a workaround that doesn't either do that or lead to bizarre type errors. -- brandon s allbery kf8nh sine nomine associates allbery.b@gmail.com ballbery@sinenomine.net unix, openafs, kerberos, infrastructure, xmonad http://sinenomine.net